JP2006027448A - Aerial photographing method and device using unmanned flying body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aerial photographing device using an unmanned flying body fitted with a camera, capable of eliminating the directional manipulation of the camera to be made by the operator, acquiring certainly and efficiently the high accuracy image data while the camera is directed precisely toward the object photographed automatically, and recording the obtained image data. <P>SOLUTION: The aerial photographing device works with the unmanned flying body fitted with the camera and a means to record the image data given by the camera, with which the distance between the fuselage of the flying body and the object to be photographed is measured during the flight, and the object is photographed upon deciding the zooming magnification of the camera on the basis of the result from measurement, and the photographing is made with the image data of the object taken in while the facing of the camera directed toward the object is changed at certain angles up and down and to the left and right during the flight. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for taking an aerial image using an unmanned air vehicle such as a helicopter, an airplane, or an airship flying by remote control (R / C) or autonomous control (A / C).

Aerial photography using an unmanned aerial vehicle can reduce costs compared to using a real airplane or helicopter, and can shoot safely even in a narrow space at low altitudes, as well as shooting close to the shooting target. As a result, high-quality photographs and video images can be obtained, and the maintenance status of structures, inspection of high places, ground observation from high places, etc. are being implemented in various fields.
As a system for performing aerial photography using an R / C helicopter as an unmanned air vehicle, for example, as shown in FIG. 8, a camera 82, a camera attitude control mechanism 83, and a camera image are transmitted to the R / C helicopter 81. Communication means 84, an aerial image processing system 85 having a means for receiving a captured image on the ground side and a storage means, and a device 86 for remotely controlling the attitude of the camera are provided and transmitted from the R / C helicopter 81. There is a known configuration in which the captured aerial video is associated with the shooting condition information and stored in the storage unit of the aerial video processing system 85 to facilitate use of the captured video (for example, Patent Document 1).

JP 2003-110981 A

In the conventional system for remotely controlling the R / C helicopter, at least two operators, that is, a person who controls the aircraft and a person who remotely controls the direction of the camera are required. Further, since it is necessary to remotely control the R / C helicopter, the flight range is limited to the range where the operator can see the aircraft, and it was impossible to take aerial photographs on the terrain where it cannot be seen or in a distant place.
Moreover, the current aerial photography of the R / C helicopter is only used for such purposes as taking a bird's-eye view of a specific area on the ground from a high place, or shooting a specific house or building from the sky. .

By the way, inspecting the surface of a structure in a high place such as a viaduct, for example, a scaffold for the inspection is built, and an operator stands on the scaffold or hangs the worker from the top of the structure to directly inspect the inspection site. In addition, inspection of the surface of the transmission line installed on the steel tower and the sleeve part of the transmission line can be carried out while the operator is traveling along the transmission line, or from the ground or helicopter using binoculars. This is done by directly observing the surface of the wire. Passengers use binoculars to check natural disaster sites such as landslides from helicopters that fly sufficiently away from the disaster site to avoid wind pressure.
Use an unmanned helicopter equipped with aerial photography for such high-level structure inspections and disaster site inspections, bring the unmanned helicopter close enough to the inspection location and increase the zoom magnification of the camera. If it is possible to obtain an image that is the same as when an operator takes a picture and observes the inspection location in the immediate vicinity, the cost required for the inspection can be greatly reduced.
However, in remote control, if the inspection location is several hundred meters like a transmission line, the helicopter cannot be controlled unless the operator moves with the unmanned helicopter due to the output rating of the propo. It is difficult to fly precisely along and close to the vehicle itself, and it is difficult to control the camera mounted on the unmanned helicopter accurately at the inspection location and capture the subject image in full frame. In fact, inspection technology for high-rise structures using R / C helicopters has not been established.

On the other hand, recently, development of autonomous control technology that controls the aircraft so that an unmanned helicopter automatically takes off from a predetermined position, flies on a predetermined flight route at a predetermined speed, and automatically returns to the takeoff point for landing. Is being promoted and put into practical use. If an autonomously controlled A / C helicopter is used instead of the remote control type for the above-mentioned inspections, the unmanned helicopter will fly to distant structures that cannot be remotely controlled or terrain that cannot be seen. Is possible.
However, the autonomous control function of the unmanned helicopter that has been put into practical use is only for flying the aircraft along the flight course set and input before takeoff, and when performing aerial photography using an unmanned helicopter, Even if the camera mounted on the aircraft loses sight of the shooting target during flight, the flight route cannot be changed to return the aircraft to the point where it was lost. When the unmanned helicopter is flying at a predetermined speed along a set course, the aircraft may tilt in any direction or the nose direction may change intermittently due to the influence of the wind. The orientation may deviate from the shooting target. Therefore, even when performing aerial photography with an A / C helicopter, a technique for controlling the camera so that the image of the subject can be captured stably over the entire frame while the camera mounted on the aircraft is accurately directed to the inspection location is essential.

  In view of such problems of the prior art, the present invention eliminates the need for the operator to operate the camera in the aerial shooting using an unmanned air vehicle equipped with a camera, and automatically sets the camera on the object to be photographed automatically. It is an object of the present invention to obtain and record high-definition video data reliably and efficiently.

  When autonomously controlling an A / C helicopter, a flight route including a flight passing point and a flight arrival point is input to the autonomous control device in advance. This flight route is specified by data such as latitude, longitude, altitude, and direction. Set by multiple flight points. The A / C helicopter is equipped with means for detecting the data, specifically GPS signal receiving means for detecting latitude and longitude, altitude detecting means, azimuth detecting means, etc., and these means sequentially detect the flight position. By reflecting the difference in position between the target flight point and the actual flight point on the drive mechanism, the aircraft is controlled along the flight route.

  Of the detection means, the detection of latitude and longitude always includes an error of several tens of centimeters due to communication with a GPS satellite. Therefore, for example, if the subject to be photographed is a transmission line whose thickness is less than 5 centimeters, suppose that the camera is placed in a predetermined direction at a predetermined flight point based on previously set flight condition and shooting condition data. Even if the directing control is made accurately, the position of the actual transmission line and the direction of the camera are shifted by the error, so the image of the transmission line is not captured, or the distance between the aircraft and the actual transmission line is Due to the large size, the zoom magnification of the camera is insufficient, resulting in a situation where a high resolution image cannot be obtained.

Therefore, in the present invention, in a method for performing aerial photography with a camera and a means for recording video data output from the camera on an unmanned air vehicle, the distance between the aircraft and the object to be imaged is measured during the flight, and the result The camera zoom magnification was determined from the above, and the subject was photographed.
According to this, when the helicopter reaches the flight point where shooting starts, the exact distance between the aircraft and the shooting object is measured, and the positional relationship between the flying aircraft and the shooting object is accurately determined. As a result, it is possible to reliably capture the image of the object to be photographed with the camera and obtain image data that has been enlarged to an appropriate size, so that it can be input as a flight position detection error or flight route included in each of the detection means. It is possible to correct high-definition video data by correcting errors in the position data.

  In the aerial photography method, in flight, in the direction of the shooting target so that the shooting target can be reliably shot even when the aircraft shakes or the direction of the nose changes due to the influence of wind during the flight. It is preferable to capture the video data of the object to be photographed while moving the directed camera up and down or left and right at a predetermined angle.

  Preferably, the aerial imaging method preferably includes an autonomous control device that allows an unmanned air vehicle to fly along a predetermined route, a flight position specifying unit that specifies a position in flight from a GPS signal, an airframe, and an object to be imaged. Distance measuring means for measuring the distance to the camera, camera control means for controlling the camera angle, zoom magnification, shooting start and end, and the shooting start position, camera angle, distance from the shooting start position to the object to be shot , Means for recording shooting condition information such as camera zoom magnification and shooting end position, and actual distance measuring means for controlling the distance measuring means at the shooting start position to measure the distance between the airframe and the shooting object. The camera zoom magnification is calculated from the difference between the actual distance to the object to be photographed and the distance to the object to be photographed recorded in the photographing condition information so that the subject has a predetermined size within the camera frame. And means for updating the photographing condition to the zoom magnification, and an imaging processing control means for controlling said each means based on the imaging condition information can be carried out by aerial device provided on the body.

  The aerial imaging device includes a unit for recording video data of a subject to be photographed, and the recorded video data is collated with video data output from a camera during photographing so that the subject of photographing is included in the video data. And a means for determining whether or not the image is included, and only the video data including the photographing object can be recorded in the recording means.

  According to the aerial imaging method and aerial imaging apparatus using the unmanned air vehicle of the present invention, the image of the object to be photographed is accurately and sufficiently enlarged within the camera frame with the camera mounted on the unmanned air vehicle. It can be recorded as high-definition video data. Therefore, it can be effectively and effectively used for inspection of the surface of a high-rise structure and inspection of a disaster site, and the cost required for the inspection by the conventional method is greatly reduced.

A preferred embodiment of the present invention will be described with reference to the drawings.
The illustrated form is an embodiment of a system that performs aerial photography for maintenance of an elevated transmission line using a helicopter equipped with an autonomous control function (A / C) as an unmanned aerial vehicle. Is an A / C helicopter equipped with a camera, 2 is a ground station, and W is an electric wire to be photographed.

  As will be described later, the A / C helicopter 1 is equipped with recording means, and the flight plan information is input to the recording means from the computer 21 previously installed in the ground station 2 at the same station, and the shooting condition information is input from the computer 22 to the recording means. The A / C helicopter 1 automatically takes off from the ground station 2 that is the starting point, and flies at the set speed based on the flight route based on the flight plan information, and is also photographed based on the photographing condition information during the flight. An image of the electric wire W, which is an object, is automatically recorded, and is returned to the starting point and landed again.

  The A / C helicopter 1 has a structure in which a rotor is rotated by a small engine and flies. An imaging device 4 for automatically tracking and shooting is mounted.

  As shown in FIG. 2, the autonomous control device 3 includes a recording means 31 to which flight plan information is input, an autonomous control means 32 connected to the rotor driving means 32a, a GPS signal receiving means 33, a distance measuring sensor 34, a route guidance. A camera 35, an altitude sensor 36, an orientation sensor 37, a communication means 38, and a control means 39 for controlling these parts are provided. Based on the flight plan information recorded in the recording means 31, the driving of the rotor is controlled by the autonomous control means 32. The A / C helicopter 1 is configured to be able to stably fly autonomously along a predetermined flight route.

  Specifically, the flight plan information sets the flight conditions such as the flight route, flight speed, flight altitude, and turning location during the period from takeoff from the departure point, flight within the specified range, return to the departure point, and landing again. Data, a processing program for controlling the rotor so as to fly under the set conditions, parameters for executing the program, etc., which are set and inputted in the computer 21 of the ground station 2 and are transmitted via the communication means 38 before the flight. The computer 21 connected to the autonomous control device 3 is transferred to the same device and recorded in the recording means 31. As described above, the flight route is configured by setting a large number of flight points specified by data such as latitude, longitude, altitude, and direction and inputting these data.

  The GPS signal receiving means 33 is a means for specifying the position of the aircraft in flight, receives GPS signals from GPS satellites, and outputs latitude and longitude data of the flight position as current position information.

  The distance measuring sensor 34 is attached to the front part of the A / C helicopter 1 and detects the distance from the airframe to the ground structure to keep the distance from the A / C helicopter 1 constant. While preventing generation | occurrence | production, it is for measuring the distance from the electric wire W which is imaging | photography object of the imaging device 4 mentioned later to the body. As the distance measuring sensor, for example, a sensor using a stereo vision camera or a distance measuring means using a laser can be used.

The route guidance camera 35 is attached to the front part of the A / C helicopter 1 to take a picture of the front of the body and output the video signal as forward information on the aircraft during flight.
The altitude sensor 36 detects the altitude of the aircraft in flight, and the direction sensor 37 detects the traveling direction of the aircraft and outputs a signal.

  The communication means 38 transmits and receives various data used for autonomous flight control with the computers 21 and 22 of the ground station 2 by wire or wireless when the A / C helicopter 1 is grounded and wirelessly during flight. In addition, the video signal captured by the route guidance camera 35 can be transmitted from the A / C helicopter 1 to the ground station 2 and displayed on a monitor installed in the ground station 2. It has become.

  The autonomous control means 32 incorporates a gyro device that detects fluctuations in the airframe around each axis of pitch, ladder, and yaw and drives the rotor to absorb the fluctuations to stabilize the flight posture. On the basis of the data output from the control means 39, the rotational speed of the rotor required for autonomous flight, the angle of the rotating surface, etc. are calculated, and a drive signal is output to the rotor drive means 32a so that the A / C helicopter 1 is stably It is designed to fly autonomously. Further, the position information in flight obtained from the GPS signal receiving means 33 and the distance information between the ground structure obtained from the distance measuring sensor 34, the altitude information obtained from the altitude sensor 36, and the direction information obtained from the direction sensor 37. Each information is input to the autonomous control means 32, and a drive signal is output to the rotor drive means 32a so as to fly along the flight route set by the flight plan information, thereby controlling the aircraft. The A / C helicopter 1 controlled by the autonomous control device 3 comes to fly along a set flight route without touching the ground structure and while turning or hovering at a predetermined position. Yes. In addition, when the flight plan information includes the video data of the ground structure that is the flight target, the ground structure that is the flight target is automatically searched from the video signal obtained from the route guidance camera 35, and is directed to the flight target. The A / C helicopter 1 can be made to fly.

  As shown in FIG. 3, the photographing apparatus 4 includes a recording unit 41 in which photographing condition information is recorded, a camera 42, an input interface 43 that converts an output signal of the camera 42, a zoom magnification of the camera 42, and photographing start and end. A camera operation control means 44 for controlling the operation of the camera, an angle control means 45 for supporting the camera 42 in the predetermined direction, a communication means 46, and a control means 47 for controlling these parts, which are recorded in the recording means 41. Based on the obtained shooting condition information, the angle control means 45 takes a picture of the electric wire W that is the subject of photography while changing the direction of the camera 42, and the continuous video data of the electric wire W is recorded while the A / C helicopter 1 is flying. 41 can be recorded. Further, the control means 47 outputs the flight position, distance, altitude and direction output from the respective detection means of the GPS signal receiving means 33, the distance measuring sensor 34, the altitude sensor 36 and the direction sensor 37 of the autonomous control device 3. Each information is input, and data processing and control of each part are performed based on the information.

  Specifically, the shooting condition information is information for specifying the position of the electric wire W to be imaged, that is, the latitude and longitude of the point where the electric wire W is installed, the altitude, the size of the electric wire, the distance from the aircraft at the time of shooting, etc. Data related to the camera, zoom ratio of the camera at the time of shooting, camera direction, camera operating conditions such as the shooting start point and end point, and a program for operating the camera so that shooting is performed according to the operating conditions And a program for processing video data captured from the camera, and various parameters necessary for executing the program. The photographing condition information is set and input in the computer 22 of the ground station 2 and transferred to the recording device 41 from the computer 22 connected to the photographing device 4 via the communication means 46 before the flight. By executing the processing program recorded in the recording means 41 by the control means 47, an actual distance measuring means 410, a zoom magnification calculating means 411, a zoom magnification updating means 412, an object specifying means 413, a direction control means 414, which will be described later, Each data processing unit includes an object determination unit 415, a reference direction update unit 416, a video cutout unit 417, a malfunction avoidance unit 418, and a system shutoff unit 419.

  The camera 42 is a digital still camera, and is supported by the angle control means 45 on the front part of the A / C helicopter 1. The video signal output from the camera 42 is input to the input interface 43 and the level is adjusted, and then output to the control unit 47 as video data. A digital video camera may be used instead of the still camera.

  The camera operation control means 44 is integrally attached to the camera 42, receives a control signal from the control means 47, converts the zoom magnification of the camera 42, and controls on / off of the shutter of the camera 42. .

  The angle control means 45 is installed at the front bottom part of the A / C helicopter 1 and the part that supports the camera 42 is a combination of a motor that rotates about the vertical axis and a motor that rotates about the vertical axis. It is configured to be able to rotate around, and is configured so that the supported camera 42 can be rotated in an appropriate direction and at an appropriate speed and directed in a desired direction. In addition, the angle control means 45 sets the initial position when the camera 42 is horizontally supported with the A / C helicopter 1 in contact with the ground, and when the orientation of the camera 42 is changed, The displacement angle around both vertical and vertical axes from the position is detected and a signal is output. The angle control means 45 can be remotely controlled by a control device 23 (described later) installed in the ground station 2.

  The communication means 46 can transmit and receive various data used for image processing with the computer 22 of the ground station 2 by wire or wireless when the A / C helicopter 1 is grounded and wirelessly during flight. It has become. The communication means 46 can also transmit and receive data between the control device 23 installed in the ground station 2 and the monitor 24 (see FIG. 4). The control means 44 can be remotely controlled to transmit a video signal photographed by the camera 42 and display it on the monitor 24.

  When the A / C helicopter 1 reaches the shooting start point, the actual distance measuring unit 410 controls the distance measuring sensor 34 described above with the control unit 47 to measure the distance between the electric wire W to be imaged and the airframe. It is means to do. The distance to the electric wire W is measured by causing the control device 23 of the ground station 2 to remotely control the angle control means 45 to display and output an image captured by the camera 42 of the A / C helicopter 1 on the monitor 24. If an image of the electric wire W is captured, a distance measurement signal is transmitted from the control device 23, and the distance sensor 35 is operated. The measured actual distance is recorded in the recording means 41.

  The zoom magnification calculation means 411 captures an enlarged image of the electric wire W in the frame of the camera 42 from the difference between the measured actual distance to the electric wire W and the distance to the electric wire W set in the imaging condition information. This is a means for calculating the optimum zoom magnification that can be used. For example, the A / C helicopter 1 flies along the flight route of the flight plan information and reaches the shooting start point, and the shooting condition information input in advance zooms because the distance from the point to the electric wire W is Xm. When the magnification was set to 2 times and the actual distance to the electric wire W was measured, when there was a deviation of (Xm + 2m) due to errors in the GPS reception signal, etc. Since shooting is performed from a distance, a calculation process is performed to enlarge the zoom magnification, for example, 2.5 times. The calculation standard can be set so that, for example, the imaging of the electric wire W having a thickness of about 3 cm occupies approximately 1/4 of the display area within the vertical width of the frame of the camera 42. . When the shooting start point is closer to the electric wire W than the shooting point set and input in advance, a reduced value is calculated as the zoom magnification.

  The zoom magnification updating unit 412 is a unit that replaces and updates the zoom magnification data in the shooting condition information recorded in the recording unit 41 with the calculated zoom magnification. Thereafter, shooting is performed at the updated zoom magnification. Done.

The object specifying means 413 performs processing for specifying the electric wire W to be imaged from the video signal output from the camera 42 and recording the video signal as video data. To identify the electric wire W, the camera 42 captures an image of the electric wire W and remotely transmits a distance measurement signal from the control device 23 while the angle control means 45 is remotely controlled by the control device 23 of the ground station 2 along with the measurement of the actual distance. When this is done, the video signal of the electric wire W output from the camera 42 is recorded in the recording means 41 as video data.
In this embodiment, the electric wire W is an object to be imaged, and an image when the electric wire W as shown in FIG. 1 passes through the center of the monitor 24 and horizontally crosses the monitor is specified as an object. Yes. For example, in the second and subsequent aerial shots of photographing the same object, the video data of the target specified in the first aerial shot is recorded in the recording means 41, and this video data is used as a reference for tracking shooting. The process of specifying the object to be photographed from the video signal of the camera 42 may be omitted.

The direction control unit 414 outputs a control signal to the angle control unit 45 and performs a process of displacing the direction of the camera 42. Specifically, the angle control means 45 uses the information on the orientation of the camera when the object is specified by the object specifying means 413 and the video data is recorded, that is, the displacement angle data of the camera 42 from the initial position described above. The control signal is output to the angle control means 45 so that the direction of the camera is displaced over a predetermined range with reference to the displacement angle data.
In this embodiment, in order to record video data of the electric wire W, the A / C helicopter 1 is caused to fly in parallel with the installation direction of the electric wire W, and a control signal is sent so that the camera 42 changes up and down along the vertical vertical direction. It is designed to output. For example, when the electric wire W that passes through the center of the imaging region of the camera 42 and crosses the imaging region is specified as the subject to be photographed, the range in which the camera 42 is displaced is the center of the imaging region of the camera 42 1 m on both the upper and lower sides of the electric wire W. The camera 42 can be set to shoot while changing the shooting angle within a range of a total length of 2 m around the electric wire W. The direction in which the camera 42 is displaced and the setting of the range are included in the photographing condition information input from the computer 22 of the ground station 2 before the flight. Note that control data may be received from the control device 23 of the ground station 2 during the flight, and the shooting range and direction of the camera 42 may be set.

  The object determining means 415 takes in the output signal of the camera 42 that continues to shoot while changing the direction as video data, and determines whether or not the object specified by the object specifying means 413 is included in this data. The process which performs is performed. In the determination process, for example, the captured video signal is converted into binarized image data with an appropriate threshold value, and it is specified that the object is included from the difference in lightness or darkness of the object included in the image data. It can be performed by an appropriate processing method such as specifying an image of an object from comparison between a characteristic shape and its coordinates. When it is determined that the video of the electric wire W, which is the object, is included, the captured video signal is recorded in the recording unit 41 as video data by the video cutting unit 416.

  The reference direction updating unit 416, when the object determining unit 415 determines that the object is included in the image data, the angle control unit 45 indicates information on the camera orientation when the video signal is captured. The displacement angle data of the direction control means 414 is updated to the acquired information. Thereafter, the direction control unit 414 controls the direction of the camera 42 based on the displacement angle data updated by the reference direction update unit 416.

The video cutout unit 417 performs a process of cutting out only video data including a shooting target from one frame of video signal that is a shooting region of the camera 42 and recording it in the recording unit 41. Specifically, the video of the electric wire W crossing the imaging area of the camera 42 is identified from the video data determined by the object determining means 412 to include the electric wire W that is the object to be imaged. In this image data, the data of the upper and lower edges that do not include the video data of the electric wire W are cut out, and since the video of the electric wire W is included, it is processed into horizontally long image data and recorded in the recording means 41. It has become.
In the recorded image data, the GPS signal receiving means 33, the distance measuring sensor 34, and the altitude sensor 37 output the position information including the latitude and longitude, distance information, and altitude information. The history of the flying position is recorded together with the image data.

  While the A / C helicopter 1 is flying, the malfunction avoiding means 418 does not have a video for identifying the electric wire W in the video signal output from the camera 42, that is, the tracking shooting fails. In this case, since effective data collection cannot be performed, the image processing by the photographing apparatus 4 is stopped, and the angle control means 45 is controlled so that the camera 42 returns to the initial position. Regardless of whether a control signal is output from the direction control means 414 to the angle control means 45, the image processing is stopped even when the angle control means 45 does not operate, and the malfunction avoidance means 418 returns the camera 42 to the initial position. The control signal is output as follows. Furthermore, even when the operation of the communication means 38 and 46 is stopped due to noise in flight or contact failure of the signal system, the image processing by the photographing device 4 is stopped and the camera 42 is moved to the initial position. Yes.

  The system shut-off means 419 performs data processing of the recording means 41 and the control means 47 of the photographing device 4 when the A / C helicopter 1 is in flight or in a grounded state and the main power of the A / C helicopter 1 is cut for some reason. The operation of the photographing apparatus 4 is stopped by using a power-off detection signal from a detection means (not shown) provided in the switch section of the main power supply as a trigger so that the section is not damaged.

  Next, a description will be given of a processing step of recording while tracking an image of the electric wire W that is a subject of photographing with the A / C helicopter 1 equipped with such an autonomous control device 3 and the photographing device 4.

  FIG. 4 shows a flight route of the A / C helicopter 1 that records an image of the overhead wire W. The A / C helicopter 1 taking off from the ground station 2 as the departure point flies to the point (a) above the tower A, temporarily hoveres at this point, and enters a standby state.

  Here, the distance between the A / C helicopter 1 and the electric wire W is measured and the reference image is captured. That is, the control device 23 of the ground station 2 remotely operates the angle control means 45 of the photographing device 4 to operate the photographing direction of the camera 42, and the video signal transmitted from the photographing device 4 (arrow a in the figure) indicates that the camera If it is confirmed on the monitor 24 that 42 has captured the image of the electric wire W, a ranging signal is output from the control device 23 to the photographing device 4 (arrow B).

  If the photographing device 4 receives the distance measurement signal, the photographing device 4 measures the distance from the machine body to the electric wire W, calculates an appropriate zoom magnification, updates the zoom magnification, and captures an image of the reference electric wire W. At the same time, an imaging flight start signal is transmitted from the same device to the autonomous control device 3. In response to this, the autonomous control device 3 flies in parallel along the electric wire W from the point (a) to the point (b) above the steel tower B, and during this time, the photographing device 4 has the electric wire W in the photographing region of the camera 42. The image data of the electric wire W is continuously recorded while tracking the electric wire W so as to be positioned at the center.

  If the autonomous control device 3 confirms that the A / C helicopter 1 has reached the point (b) based on the flight position information output from the GPS signal receiving means 33, the distance measuring sensor 34, and the altitude sensor 36, The / C helicopter 1 switches to a flight that hoveres at point (b) at the same time, and simultaneously outputs an image processing stop signal from the autonomous control device 3 to the photographing device 4, and the photographing device 4 stops the recording processing of the image data, and the camera 42 is returned to the initial position. (B) When the A / C helicopter 1 arrives in the vicinity of the point, the tracking shooting of the shooting device 4 may be set to stop.

  Thereafter, the A / C helicopter 1 autonomously flies from the point (b) to the ground station 2 that is the starting point, and automatically lands on the ground station 2. The above-described flight operation of the A / C helicopter 1 is automatically performed in the ground station 2 based on the flight plan information input from the computer 21 to the recording means 31 of the autonomous control device 3.

  The capturing and recording of the video data of the electric wire W from the point (a) to the point (b) is performed by the photographing device 4 as follows.

  As described above, in the state where the A / C helicopter 1 is hovering at the point (a), the control device 23 of the ground station 2 is remotely operated to set the camera 42 to the direction of imaging the electric wire W, and When the monitor 24 confirms that the image of the electric wire W is located at the center, a distance measurement signal is output from the control device 23 to the photographing device 4. Upon receiving the signal, the photographing apparatus 4 measures the actual distance to the electric wire W by the actual distance measuring means 410, calculates an appropriate zoom magnification based on the distance measured by the zoom magnification calculating means 411, and zoom magnification updating means. The imaging condition information is updated to the zoom magnification calculated in 412. At the same time, the video signal output from the camera 42 is recorded as video data in the recording unit 41 by the object specifying unit 413, and at the same time, the direction control unit 414 takes in the camera orientation information from the angle control unit 45.

  And while the A / C helicopter 1 flies from the point (a) to the point (b), the angle control means 45 is controlled by the direction control means 414, and the camera 42 is swung up and down along the vertical vertical direction. The video data is captured while the electric wire W is being tracked. As shown in FIG. 5, the swing control by the direction control means 414 is based on the direction of the camera 42 (Fc in the figure) in which the electric wire W is located at the center of the area F in the imaging area F of the camera 42. This is performed so that the camera 42 swings the head by a predetermined range above and below the electric wire W, for example, an interval of about 1 m above and below. As described above, when the video data of the electric wire W that is the target is captured by the target determination unit 415, information on the camera orientation that is the reference for swinging is updated. The head swing control is always performed around the electric wire W toward the periphery thereof, so that even if the body is shaken during photographing and the photographing direction of the camera 42 is shifted, the video data is taken again in the reference direction, and the electric wire W is taken. The image data tracked in the can be obtained.

  After the video data of the reference electric wire W to be imaged and the reference camera orientation information are recorded by the object specifying means 413, the direction control means 414 changes the direction and changes the direction in the video output signal of the camera 42. The object determining means 415 determines whether or not the electric wire W is included.

  The determination can be made by a video data processing procedure as shown in FIG. 6, for example. That is, first, in the figure, the video signal of the camera 42 input to the control means 47 via the input interface 43 is corrected in S1.

  Next, in S2, filter processing is performed to absorb image quality due to individual differences in cameras and weather differences at the time of shooting. In S3, vertical edge detection processing is performed, and the wire W taken in a direction across the camera 42 is processed. The outline is emphasized.

  The video data subjected to the edge detection process in S4 is subjected to Hough transform, and in S5, it is determined whether or not there is a straight line crossing in the horizontal direction in the imaging region. If there is no crossing straight line, the next video data is captured and processed, and if there is a crossing straight line, it is determined that the video data is for the electric wire W, and the Y coordinate of the pixel having the video data of the straight line is detected in S6.

  On the other hand, while the presence / absence of the image of the electric wire W is determined, the video signal corrected in S1 is subjected to delay processing in S7, and the video data subjected to this delay processing is determined based on the detected Y coordinate in S8. Then, only the video of the electric wire W is cut out, and the horizontally long data string of the electric wire W cut out in S9 is recorded in the recording means 41.

FIG. 7 shows a state in which the video data of the electric wire W processed by the above procedure is recorded when the camera 42 is swung from the upper side to the lower side around the electric wire W to capture the video data of F1 to F12. .
As shown in the drawing, when the camera 42 is swung and photographed, an image of the electric wire W is photographed at F4 to F9. Of these, it is determined in S5 of the processing that the video data of F6 and F7 includes the video of the electric wire W crossing the imaging region. As described above, when video of the electric wire W is included in video data of a plurality of frames in one swing operation, the video data of F6 where the electric wire W is located at the center of the imaging region is recorded as data to be recorded in the recording unit 41. select. Then, in the video data of F6, the data of the upper and lower edges not including the video of the electric wire W, which is indicated by hatching in the figure, is cut off, and a horizontally long data string including only the video data of the electric wire W is stored in the recording means 41. Will be recorded. The video data recorded in the recording means 41 incorporates data such as the latitude, longitude, altitude, etc. of the flight position of the A / C helicopter 1 output from the GPS signal receiving means 33 or the like.

  Simultaneously with the determination and recording of the video data including the electric wire W by the object specifying means 413, the reference direction update means 416 updates the camera direction information of the direction control means 414, and thereafter the flight A / Until the C helicopter 1 reaches the point (b), the determination and recording of the video data are repeated while changing the direction of the camera 42 to track the wire W with reference to the displacement angle data updated as needed. Record video data.

  When the A / C helicopter 1 returns to the ground station 2 that is the departure point, the video data recorded in the recording means 41 is transmitted to the computer 22 of the ground station 2 via the communication means 46 of the photographing device 4. In step 22, further video data analysis processing is performed. The recording unit 41 of the photographing apparatus 4 may be provided detachably, and the recording unit 41 may be directly connected to the computer 22 to process video data. Further, the recording means 41 is provided with a portable data recording medium such as a memory card, video data is recorded on the data recording medium, and after the A / C helicopter 1 has landed, only the data recording medium is removed and recorded. Data may be read by the computer 22.

In the illustrated embodiment, an example in which a photographing device is mounted on an A / C helicopter having an autonomous control function has been shown. However, the present invention is mounted on an R / C helicopter that flies by remote control. This is also applicable to aerial photography.
Although the autonomous control device and the photographing device are provided separately, they can be configured integrally. Depending on the shooting target, the camera is swung in the left-right direction or an arbitrary direction, and the video data is taken in appropriately while changing the shooting direction continuously or intermittently.
Further, the configuration and function of the processing means constituting the photographing apparatus are merely examples, and may have other appropriate configurations and functions, or may be combined with other processing means.

It is the figure which showed the structural example of the system which takes aerial image with the aerial imaging apparatus of this invention. It is the figure which showed an example of the structure of an autonomous control apparatus. It is the figure which showed an example of the structure of the imaging device of this invention. It is the figure which showed the flight route of the A / C helicopter which records the image | video of an overhead wire with the system of FIG. FIG. 5 is a diagram showing a state in which a camera is operated to record video data of electric wires during flight along the route of FIG. 4. It is the figure which showed the determination processing procedure for recording the video data of an electric wire. It is the figure which showed a mode that a camera was swung around the electric wire and video data was recorded. It is the figure which showed the structure of an example of the conventional aerial imaging apparatus.

Explanation of symbols

1 A / C helicopter, 2 Ground station, 21, 22 Computer, 23 Control device, 24 Monitor, 3 Autonomous control device, 4 Shooting device, 42 Camera, W wire, F Shooting area

Claims (4)

In a method of performing aerial photography with a camera and means for recording video data output from the camera on an unmanned air vehicle,
An aerial photography method using an unmanned aerial vehicle characterized in that a distance between an airframe and an object to be imaged is measured during flight, and a zoom magnification of the camera is determined from the result to image the object to be imaged.   The unmanned aerial vehicle according to claim 1, wherein the image data of the photographing object is captured while the camera is directed in the direction of the photographing object while the flight is displaced at a predetermined angle vertically or horizontally. Aerial photography method. An aerial imaging apparatus for carrying out the method according to claim 1 or 2,
An autonomous flight control device that allows an unmanned air vehicle to fly along a predetermined route set in advance, a flight position specifying means that specifies a position in flight from a GPS signal, and a distance measuring means that measures the distance between the airframe and the object to be photographed And camera control means for controlling camera angle, zoom magnification, shooting start and end, etc., shooting start position, camera angle, distance from shooting start position to shooting object, camera zoom magnification, shooting end position Means for recording the photographing condition information such as, actual distance measuring means for controlling the distance measuring means at the photographing start position to measure the distance between the aircraft and the photographing object, and the measured actual distance to the photographing object The zoom magnification of the camera is calculated so that the subject has a predetermined size within the camera frame from the difference from the distance to the shooting target recorded in the shooting condition information, and the calculated zoom magnification is Aerial apparatus using means for updating the shadow conditions, the unmanned air vehicle, characterized in that an imaging processing control means for controlling said each means based on the imaging condition information provided on the body. The means for recording the video data of the shooting object and the recorded video data are compared with the video data output from the camera during shooting to determine whether or not the shooting object is included in the video data. The aerial imaging apparatus using the unmanned aerial vehicle according to claim 3, further comprising: a recording unit configured to record only video data including a photographing object in the recording unit.

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